A double labial-arch retaining appliance to retain the treatment effective of Class III osteal malocclusion were introduced and used to retain 60 patients with Class III osteal malocclusion. At the same time, 60 patients with Class III osteal malocclusion were retained with conventional Hawley retainer as the control group. The results indicated that the double labial-arch retaining appliance has good effect to the retain of Class III osteal malocclusion.